Halevy Itay, Zuber Maria T, Schrag Daniel P
Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA.
Science. 2007 Dec 21;318(5858):1903-7. doi: 10.1126/science.1147039.
Ancient Mars had liquid water on its surface and a CO2-rich atmosphere. Despite the implication that massive carbonate deposits should have formed, these have not been detected. On the basis of fundamental chemical and physical principles, we propose that climatic conditions enabling the existence of liquid water were maintained by appreciable atmospheric concentrations of volcanically degassed SO2 and H2S. The geochemistry resulting from equilibration of this atmosphere with the hydrological cycle is shown to inhibit the formation of carbonates. We propose an early martian climate feedback involving SO2, much like that maintained by CO2 on Earth.
古代火星表面存在液态水，且大气富含二氧化碳。尽管这意味着应该形成大量碳酸盐沉积物，但尚未检测到这些沉积物。基于基本的化学和物理原理，我们提出，大气中存在可观浓度的火山释放的二氧化硫和硫化氢，从而维持了使液态水得以存在的气候条件。这种大气与水文循环平衡所产生的地球化学特征表明，它抑制了碳酸盐的形成。我们提出了一种早期火星气候反馈机制，该机制涉及二氧化硫，类似于地球上由二氧化碳维持的气候反馈机制。
